Robust bit check by Wera. Bit checks provide a quick overview of the existing tool. Unnecessary bits are simply put back into the assortment and are not lost. Easy to carry, for example: in a shirt pocket. The Hex-Plus profile provides larger contact surfaces on the screw head. As a result, the notch effect is reduced to a minimum, the destruction of the screw head is almost eliminated. Durable for universal use. Includes universal mounting bit holder with external 1/4" hex drive according to DIN ISO 1173-C 6.3. With quick-change chuck for quick bit change. Strong permanent magnet keeps bits bomb-proof.